by creativity we mean language is resouceful owing to its duality and its recursiveness. Peculiar to human languages，users of language can understand and produce sentences they have never heard before. “ A red-eyed elephant is dancing on the hotel bed”

----Language can be used to refer to things, which are not present: real or imagined matters in the past, present or future, or in far-away places. Displacement enables people to handle generalizations and abstractions.

Systematic---- rule-governed, elements in it are arranged according to certain rules; can’t be combined at will. e.g. *bkli, *I apple eat.

Arbitrary---- no intrinsic connection between the word and the thing it denotes, e.g. “pen” by any other name is the thing we use to write with. “A rose by any other name would smell as sweet”----Shakespeare
2. Phonology----sound patterns of languages (the rules governing the structure,distribution, and sequencing of speech sounds and the shape of syllables) Distinctions between phonetics (chaos )and phonology(order)
Morphology----the form of words It studies the minimal units of meaning and word-formation processes. 4. Syntax----the rules governing the combination of words into sentence. E.g. The children watched the firework from the hill.

It
refers to the property of having two levels of structures: units of the primary level being composed of elements of the secondary level and each level having its own principles of organization. Lower level----sounds (meaningless) Higher level----meaning (larger units of meaning)
From these explanation we can conclude that language can be defined as a means of verbal communication. It is instrumental in that communicating by speaking or writing is a purposeful act. It is social and conventional / arbitrary in that language is a social semiotic and communication can only take place effectively if all the users share a broad understanding of human interaction including such associated factors as nonverbal cues, motivation, and socio-cultural roles.
1. Phonetics----speech sound
(description, classification, transcription) which includes three levels: Articulatory phonetics, Acoustic phonetics, Auditory phonetics. Channel Speaker ……… Listener
5. Semantics----the meaning of language (when the meaning of language is conducted in the context of language use----Pragmatics) 6. Pragmatics---the study of meaning in context the study of the use of signs and the relationship between signs and their users.


Vocal---- the primary medium is sound for all languages; writing system came much later than spoken form.
Human-specific---- different from the communication systems other forms of life possess, e.g. bird songs, bee dance, animal cries Arbitrariness Duality Productivity/Creativity Displacement



Webster’s New World Dictionary offers several most frequently used senses of the word “language”. [1] (a) human speech (b) the ability to communicate by this means (c) a system of vocal sounds and combinations of such sounds to which meaning is attributed, used for the expression or communication of thoughts and feelings; (d) the written representation of such a system [2] (a) any means of expressing or communicating, as gestures, signs, or animal sounds (b) a special set of symbols letters, numerals rules etc. used for the transmission of information.

Applied
linguistics----linguistics and language teaching social factors (e.g. class, education) affect language use behavior
Sociolinguistics----
Psycholinguistics----linguprocess
Anthropological linguistics: anthropological linguists are interested primarily in the history and structure of formerly unwritten languages. Computational linguistics (e.g. machine translation): an interdisciplinary field which centers around the use of computers to process or produce human language.


许国璋先生认为把语言定义成交际工具不够科学, 至少不够严谨.他对语言的定义做了如下概括:语 言是一种符号系统. 当它作用于人与人之间的关系的时候,它是表达 相互反应的中介; 当它作用于人与客观世界的关系的时候,它是认 知事物的工具; 当它作用于文化的时候,它是文化的载体



Oral language: a human natural language in which the words are uttered through the mouth. Written language: a conventional system of graphic signs (or letters),compared to spoken English. Sign language: using the hands, arms, and face rather than parts of the mouth as their place of articulation.